Incubator



April 13, 1948. R. B. P.' cRAwFoRb Incuuon Filed vsept. 2o, 1943 4 Sheets-Sheet 1 hlwlllllllt yApril 13, 194s. R. e. P. cnAw'FoRn INCUBATOR Filed Sept. 20, 1943 lLSheets--Sheet 2 IApril 13, 194s.

R.` B. P. cRAwFoRD INCUBATOR AFiled sept. 2o, 1943 4 Sheets-Sheet 3 A Pl'il 13, 1948. R. B. P. cRAwVFoRD 2,439,719

INCUBATOR Filed Sept', 20, 1943 4 Sheets-Sheet 4 5km. Y

msm

AKM

Gttorneg Patented Apr. 13, 1948 OFFICE s INCUBATOR Robert B. P. Crawford, Kansas City, Mo.` t Application September 20, 1943, Serial No. 503,067

This application is a continuation in. part of mycopending application, Serial No. 285,7 36, flled July"21, 1939, now Patent No. 2,334,865, issued November 23, 1943.

s s This inventionirelates to an airconditioning t system and while ithasbeen shownand described Withparticular referenceto the conditioning of `an egg incubator, itshould be understood that many of the features thereof are of utility in the conditioning of structures in general.

`In the hatching of eggs, the number of chicks that' are hatched for agiven numberoffertile eggs depends upon the maintenance of proper conditions of temperature and humidity during the various stages ,of incubation. ['I'hus, during the early stages of incubation, it may be necessary to supply heat tothe eggs to maintain them at",` the', proper temperature ofy approximately A100 F. During thelatterstages of incubation, the" eggs generate a large `'amount of heat and it may be necessary to cool these stages to maintain the temperaturethereof at the proper value.` In

accordance with the. teachings of my invention, theeggs are carried through the incubator by means of a beltwhich requires approximately. twentyfone days' for the eggs` to move from one end of the incubator' to the other. The ,incubatorma'y be divided into Vseveral stages, as for exampleseven stages 'inleach of which the eggs remain for three days. VSuitable heat exchanger coilsl areprovidedin the Wallsof each stage,`

and through these coils Water or other suitable heat` exchanging fluidfis circulated,` the water absorbing heat from the latter stagesV and giving this heatiup to the` earlier stages, the flow of Water ,through the various stages being con-` trolledfby'means of thermostats located in `each stage,4 in the more specific embodiment of my invention; l i

Under many conditions it maybe necessary to additionally heator cool the Water, and for thispurpose a refrigerationwsystem is provided, the evaporator thereof providing the necessary cooling and the condenser thereof providing the necessary heating. By reason of the fact that the heat generated in the latter stages is used to provide heat in the early stages, the necessary additional heating or cooling may be effected by` thefprovision of a refrigeration system of relatively small capacity. Another factor in increasing the yield of chicks from a given number of fertile eggs is in maintaining the air in the incubator in a condition of purity. ThisV is generally doneby circulating fresh air through `the incubator, but previous 16 Claims. (Cl. 119-41) practice. has required the circulation `.olf a large volume;` of "air through the incubator,` since the air alsoserved to maintaindesired temperatures in various portions thereof. It has also been the practice to recirculatea large amount of the airtoreduce the operating expensefof the systems. 'Ihe circulationM of the air has resulted in the spreading of ,germs fromegg to egg, and chemicals :usedto reduce the germ concentration of the air have resulted in the killing of a number of embryochicks. In accordance with my invention, since most of the heating and coolingfis effected by the use of the coils afore` mentioned, the -circulation of` air to effect the heating and cooling is unnecessary, and only suiicient` airfneed `be oirculatedto maintain the humidity at' the proper 'value and to maintain the air in a clean condition and to removeV the `excess, CO2 "and Hzovapor formed during the incubating processl` llhe air is passed `over the heat Aexchanger coils and upwardly through the conveyor belt and is exhausted through the upper portion of the casing. The conveyor belt is so constructed that-the airpassing over one egg is unable to contact any other egg, and thus the spreading of germs from egg to egg is mini- ,mized.-

Provision is also made for testing the eggs passing through theincubator and ejecting the sterile eggs before they have been in the incubator for too long a `period of time so that the eggs may be used for a useful purpose, such as the manufacture of egg powder. i Provision is also made `for, cleaning` and sterilizing the belt as it leaves the incubator, so that as the belt enters the incubator and eggs `are delivered, thereto,

it will be free of dirt and germs.` i

In addition to the featuresenumerated above, means for accurately controlling the humidity in the incubator are employed. Also, the eX- cess sensible and latent heat removed by the air leavingthe incubator maybe imparted to the air enteringthe incubator, thusincreasing the operating elciency of the system, and permitting fresh air` only toenter the incubator,` without increasing to anyappreciable extentthe operating expense thereof".` V

Itis accordingly an object of `my invention to provide anegg incubator embodying the various features `outlined above and othernovel features set forth `in the accompanying `speciication and claims.

Another object of my invention is the provision of a novel control arrangement for an air conditioning system. l

egg ej ecting Figure 4 is a View in cross section of a portion` of the egg carrying belt,

Figure 5 is a fragmentary toplviwwithcetam 4 29, may be formed of suitable porous material which permits air to flow readily therethrough. The outer walls 30 of the incubator` may be formed of any suitable heat insulating matrial and these walls are spaced from the inner walls by means of the passages 3| and 32. A fan 33 driven by a motor 34 causes air to flow by means of the passageway 3| through the lower wall 29 oi thefincub'ator and-.fthefairf passes upwardly through vthe ebelt Il an'dpas't the eggs carried thereby, through the upper wall 28 and leaves the incubator by means of the passageway 32 separating the wall 28 and the upper outer wall of theincubator. Passages 3l and 32 may be tan peredyasvshownfso as to equalize the flow of airv parts shown in cross sectionothe 4eggcarrying#` belt,

Figure 6 is a cross sectional View of theclean-i ing means for the beltf. and

Figure i 7 'is 'a`l View:V withzice'rtain partsf'shown in 'cro's'ssectinfofasimpliedfoimfof 'conditm ing. systemfe'rlnbodyigfthe principlesintmyziiivenL tion-i. y

Referring Lnio'r parlticlarlly'ti Figu drawings-thefrfeii guide the, beit therehrug and" ing Stem-e' eggs=fimm@thebeX y the' incubator by way ifthfufiwayfl'inf manner'to be later set The travel offthe'beltthrougf thejincbator is of suchspeedltiiat it"requmsapprinfnateiy twentyone'days'ir iie'gg `tottravel"frcfinft-loe entrance I6 of theincubator-t eeri'tl'l.' The incubator for puposies'pf"illustration is shim/'n asbeingK divided vinto' 'Fs'evei stages 20,] 21,122, 23,

2a, 2s; .and .26; im .each df which 'stages the eggs remain for a peridgof lapp'roiimately:t three days. Suitable means well knowrtl'iefartfmay be provided for loading the eggs on the-beltl'l and removing 'the .chicksrom the belt --as they leave the incubation Suitable means z'l may'also-be provided for uscrubbing Aand disinfecti'ng `thiwbel't after it leaves the incubator, one preferredfcon-v struction of suchmeansf shown Ain lvFig.. 65 .being more fully disclosed hereinafter.ll

The interior walls ofthe ncub'atingclamber,

as illustrated by the referenceV characters V28"`anc`l d--by' the through the incubator at various distances from theifanil 'Ilefai'rpasses to the fan 33 by means of-thg chamber 35 carrying a heat exchanger coil 36, a passageway 31 which connects the chamber 35 with a Asecond chamber y38 carrying suitbiefhumrdifyigcand' denuniifying means to 'be later'usciribedg the-neat 'exchanger Aoand th'iassagwayl t the 'fan inlet. The al? laV ing the-incubator by way, of "th`e`p"as`sagewayi'32 p'as 's'dwwardlythrouhthe ejhani 41""past the heat "anger 'Aliwherebytlie ai -excnange'rela nship j'cubatorbywaylof the not forme-'p pps for 'the' purpose ofi main? taininglthe air within the incubator inastateof 'passingr Referring now to Figure Zthe circuits for controlling the valve..6| are shown in detail. :The valve6l is` operatedby a proportioningn motor of the type illustrated in Patent 2,028,110 issued to D. G. Taylor January 14,;1936. This motor may be connected to the valvebymeans of the arm 66 operated by the motor and the link` 61 connecting the arm 66 to the stem of valve 6|. The thermostat 63 is shown to` comprise a bellows 10 provided with a suitable volatile fill which causes the bellows to expand or contract in accordance with variations in: temperature in the space in which the bellows `is mounted. The bellows controls the position of a slider arm 1 I l which cooperates with a potentiometer resistance 12, the arm 1| being connected to an arm 13 biased into engagement with the bellows by the spring 14. The controller 64 is shown to comprise a manually operated slider arm 16 which cooperates with the resistance 11 which may have suitable indicia thereon to 'correspond to the number of eggs within the incubator. As stated above, this arm may be manually adjusted in accordance with the number of eggs in the incubator or automatically controlled in any suitable manner..

Mounted in engagement with the inlet pipe 62 which conveys the waterfto the pump 60 is a bulb 80 connected by the capillary tube 8| tothe bellows 82, this tube, bulb, and bellows being `'provided with a suitable volatile fill and thebellows 82 controlling the position of the slider arm 83 which cooperates with the potentiometer resistance 84. Upon an increase in the temperature of the water in the pipe 62 the slider arm 83 moves to the right and as the temperature decreases the slider arm will move toward the left. The R terminal of the motor 65 is `connected to the slider arm 83 by means of conductors 85, 86, 81 and the center tapped resistance 88. The left side of the resistance 84 is connected to the` W terminal of the motor 65 by means of conductors 90 and 9| whereas the opposite extremity of resistance 84 is connected to the B terminal of the i motor 65 by means of conductors 92 and 93.V As

the temperature of the water in the pipe 62 decreases the arm 83 will move toward the left thus decreasing the resistance between the R and W terminals of the motor 65 and thus causing the motor to move the valve towards closed position and decreasing the supply of water to the pump 60. Conversely as the temperature of the water increases the resistance between the R and B terminals of the motor will decrease and the valve 6| will be moved towards open position.

The right end of resistance 12 of the thermostat 63 is connected to the B terminal of the motor by means of conductors 93, 92, and 95 whereas the opposite end of this resistance is connected to the W terminal by means of conductors 9|', 90, and 96. Theslider arm 1| is connected to the R terminal by means of conductors 85, 86, 98, variable resistance 98, and conductor |00. The provision of the resistance 99 in the circuit to the slider arm 1| ren-ders this control arm less sensitive than the control arm 83 and the effect of a movement of the arm 1| in response to a variation in the space temperature is to shift the control range of the arm 83. In other words, a movement of the arm 83 through a distance D has as much eiect on the valve 6| as the movement of arm 1| throughout the total extent of its range. As the space temperature increases and arm 1| moves toward the right,

l.the control range D of the arm 82 is moved toward the left and this causes the valve 6| to operate to maintain a' lower ,water temperature. The `provision ofthe centery tappedfresistance 88 insures that the. length .o ff the control `range D of the control arm 83will be `the same regardless of the positionof the control range as adjusted l'i'th'e thermostat |53` as well as the potentiometer i The right end of resistance 11 is connected by means of conductors 93 andl |02 to the B, terminal of the motor whereas the opposite `end `of this resistance is `connected by conductors 91. and `|03 to the Wterminal` ofthe motor. 1; `The R terminal of the motor is `connected to the control arm 16 by means of conductors 85, |05, and variable resistance |06which renders this control arm less sensitive than the control arm 83 and a change in the `position of this control arm 'I6 acts to shift the range of the 1arm83. 'Thus `as arm 16 is shifted toward the right` in response to an increase in the number `of eggs in the incubator, the control `range ofthe Varm 83 ,will be shifted towards the leftand valve 6| will operate to regulate the flow 0f water to` maintain the temperature of the water entering the pump `E50 at alower value. l i f; y

It will now` be apparentgthat the pump60 will cause a circulation of varying amounts of water in a manner to maintain the temperatureof the water passing to the pump at aydesiredivalue and which value is decreased as theltemperature of the space in which the incubator is located is increased or as the number of leggs in the incubator increases, and this water temperature will increase as the space temperature decreases or the number oi eggs in thelncubator decreases. The effectiveness of the control arms 1| and 16 may be readily varied by adjusting the variable resistances 99 and.|06. i Y o The motor 65 also operates an armi l0 carrying a mercury switch which is .in the circuit to the pump 60 and causes this pump ,to stop should the valve` 6| move to a substantially closed position where heat transfer would be ineffective. Line wires ||2 and |13 connected to a suitable source of power (not shown) are provided for supplying power to the pump4 60 and to many of the other Vcontrol devices as will be understood. When the mercury switch` |||.is, in circuit closing position power is supplied to the pump 60 by way of the `following circuit: from the line wire ||2 through conductors ||5, IIS; I1, switch conductor H8, pump., 60, conductors H9, |20, |2I, and |22v to the line wire ||3. When the valve 6| has been moved` to closed `or substantially closed position the switch l rwill be tilted to open position and the above described circuit to the pump 60 will be interrupted and thetpump will stop operating.l

The cooling, and heating of the water used` in thevsystem is effected by a refrigeration system which is shown to comprise `a compressor |30 driven by a motor I3 the compressor being` connectedby a pipe I 32`to a condenser |33 zfrom which refrigerant flows by-way of pipe` |34 and Aexpansion .valve |35, which isillustrated as a conventional type of thermostatic `expansion valve, to the evaporator |36, the refrigerant returning by way of the pipe |31 to the `inlet of the compressor |30. The Vcondenser |33iis utilized for supplying the necessary heat to the water used for heating and humidifying `pur- '130 is' illustrated: mi detaiirisooate i' near' 'tire exitofftneinsubatoris a hemosta ls which 'operates'aste'controllaY Vgie ally-Fd fi'gnat'edat 'etli- Th'e 'thermostatal's shown to comprise :at bmbf 1| |10- oenne'cteci'. by' the' capii-lary" 142 tothe; bellows :lil-3,itnesef elementsfbeingrprovied with a suitable volatile fill and the bellows controis-tha position ofi tHelsl-ider.' arm M11 'which Ac(ieperetes with resistancel V452 `for.''ooritr`-o11ingenio position: ofi' 'the proportion'ing': m'otorirzle. The shafty 141|:- o'fu rifio't'or4 'me controls `'fhev.position sofi ia cam'. |48 for-'azpu-rpose tobeiater described and ai. seco'nuf carn-` |=50f controlling' :the positioria o'i: a mercury switciia 15'1' w'h'ioiii controls t'h'e. com'- pressor.' operation m11 cooperation: with switoii'es 152i and 153i' which .respondl to' the:- pressure on the suction side" of the'..o'empres'sor.L

The position otlfe 'svi'tehlxlZis-i controlled by the bellows',l |55? whichisI-in communicatiern with the 'pipe '|31'. l-eadingi 1to1 the -suctioni side of. the oorrlnress'or` and" the; position Loir' :the switch?, |153 is.' controlled by thefbeilows' 156 wine-huis V`alsofiri communication' with" the*pi-ipe;` |315 'Tn' .switch |52 Als-V arrangedi to' bei moved to.' circ' breaking position when the suction pressure;v fallsf below 6'0 lbs. for' example whereas'. the swit'oii.' les' remains clos-edf until` the surii'fionc pressure failsto some lower vvalue suon' atzi 1bs; 'For'control'ling the operation of the'. compressor motor-|31, relays' |58: andi 1591. aresprovided.; en'erglzation' of either relay oaus'ingfoperationof theoonipressor motor as wilib'eoom'e' apparent. 'Ine relay.' |53 comprises ai relayV coil tllliani armature '|i-|-,.l a switch' arm |61- cooperating with` affixezroontact |153- Whenitnearielay coil.' Ito 'isrenersizea the a'rm |62' is moved into? ensagementfwi-tn tii'e contact |63,` and' when.f the. ooi1 is deenergized the arm moves out of engagement*withztli-eicontact un'der 'the influence' orig-rarity orianyssuitable biasing'mea'ns (notishowri) "Ene 'relay' 158;' comprises the relay Vcoil-*11H13Aa'rr'nature' time and-'switch arms |"1'lY and? 168.- cooperating" with: ti'e.- 'Xe'd contacts' |69 and: lfl n; Thesen armsf are: arranged toen'gag-e their respective contacts when therelay isV energized and to move' out of engagement therewithup'on d'e'en'ergizationl of the relay. Potterg is" supplied' tol these.- relays.' loyI means of 'a step-down transformer lflrl Vwhich transformer (includes a high tensioni nrimaryv li2z'conne'cted across'. the.` line'- Wires 1.113" andi lr'lliifleaingto* a suitable source of power' (not :show-ni k-tlie Atransformer" also" including-ai lowl tension. secondary [Til "Illie'car 1501controllewlbyf'ltlie st'ep. controller |4511' in: response tol variations in 'temperature in the 'space' vnieves f alclookwise directioni up'onra risein ter'riperatureV andli'f v'trietendieratn-re-in? tii'e incubator rises to 98 F. attltlieflo'cationlof the bulb'. '1411; the cammovesitli'e mercriryswitcii 45 'intel' a positionl wherein'- the contactstait-ther'fletf 181i; motor" tt,k and: conductor 1E85'- to the. 'line Wire 113i. `"Iile i c'omaressor-, lWilliK now r 'be' placed intnoperation' and' will continue-'operating as long tl'ef. tenir'xifal'ur'eV at tlrieY bulb 1'40? isabove'19'8", untillthesuctinibressureonthe compressor drops below aipredetermined-Value such as `60 lbs. 1

Should? theftemperature 4in' the-incubator at :the bullo: '1M ynovi/"drop beloW 98"y the cam'll''will loe. rotated' 'counterclockwise 'and the` mercury .'swltc'lil 1.511 i will 'move back to 'the position" shown. Itthe ten'ipeature.` in .theY incubatoradjacent' the exitrthereofat'the bulb `Ulli dropstoa stilllower value such' as"9.5' F; whch'willnormally happen Wlenrtnere are Very few' orno'Y eggs-in' the latteri'stagesf of the incubator, the cam' 'lill'will .be rotated counter-clockwise still further until tact: Ithusf 'establishing the followingcircuit torth'e'f'compressor motor |311; from limewire I'l 'throug'l'i conductor'lll( switch arm' 1&5?, Contact it; conductors 191., 184'-, motor' 13 l 'and conductor |85 totleflin'e Wire 1'13. rElie compressor Willfn'ow .start Aoperating .a'ndwill continue 'to operate until tfiesuctionrressure drops to 'a predetermnedlow value" sucli asf BZ-"l'bs, whereupon the mercury switzhlB':'Wiliflo'emoveii'to 'circuit-'breaking positionl ndthecompressor will 'shut down'. The

-swt'ohil'r be' arranged Witi'i'za relatively ,Wide cli'fiierntialfby any's'u-itable'means Weil" known in -the al'tfso. tliat'it willnot move back to circuit Ialing `position 5 until'- the' suction pressure has risento soine'rvalue" such'a's'@ lbs; After the-suctidnnressure hasrisen totifiis` value and the switch 'llha's'rnoved mack-to. tlu'spositio'n the `'compressori' will Lagain operate" untill the suction pressure 'dropsf'below"the-predeterminetl lovv value 0F32 lbss, forexampl'es 'This'operation of the 'compresti'iefevaporatbr 'l'Sa-surrounded'by wheat exchange lexchangerfvvii'ene'x'ferthe relay l'59is energized, the How "on heating; medium through" this coil'being rdoll' libel/control? of'a valVe'v 't .y'suitable -nieanssu'clfi'basiazsolenoid i 9i' ina-y b'eiprovided for coritiblHngPthfezvalve 1%; energizati'onio'f the solf enoid-vfnotmgvthezvaivato' openpo'sitiongthe van@ 'moving .to close'dlpositioni when' the solenoid is suitable biasing1:'meansl` (not shownf.' When'tlie It will now be seen that whenever the compressor motor 3| is placed in operation by reason of a low temperature at the controller |39, the valve |96 is simultaneously opened, thus permitting the iiow of heating medium through the heat exchanger |95 and thereby heating the evaporator |36. Since the solenoid |91 is controlled by the relay |59 this valve will remain closed whenever the relay |59 is deenergized so that when the compressor is in operation by reason of the temperature at the controller |39 being above 98 F'. no heating medium will be supplied to the coil |95. The purpose of this arangement will become apparent as the description proceeds.

The cam |48 of the step controller |4| controls the position of a mercury switch 240 which is shown as being a double ended switch, and in the position illustrated, the contacts at the right end thereof are closed. In this position of the switch the vallveJ24| which is located in the pipe connected to the outlet of the pump 60 will be energized through the following circuit: from the line Wire ||3 through conductor 245, the contacts at the right end of switch 240, conductors 246, 241, valve motor 248, conductors 249 and 250 to the line wire ||2. The energization of the valve motor 248 which may be inA the form o1 a solenoid or any other suitable form of motor causes valve 24| to move to open position. As the temperature in the incubator increases, cam |48 will rotate in a clockwise direction, and when the temperature has risen sufficiently, the cam will move the switch to its opposite position wherein the above described circuit to the valve `mot`orl248 is interruptedand this valve 24| `will close under the influence of gravity or any suitable biasing means. As shown in Figure 1, this valve is located in a Icy-pass around the cooling coil 255 in the tank 256 housing the evaporator and which coil is arranged to be cooled by the evaporator coil |36. It will be understood that resort may be had to any suitable arrangement for securing a suicient heat exchange relationship between the evaporator coil |36 and the coil 255 and as illustrated, the heat exchange medium in the tank 256 surrounding the evaporator |36 serves this purpose; When the valve 24| is closed water may circulate from the pump through the cooling coil 255 and be cooled thereby but when the valve 24| [is opened the water may by-pass this cooling coil and not be cooled appreciably thereby. The mercury switch 240 also "controls lthe position of a pair of valves Y260 and 26| for a purposeftobe later set forth.' These valves are shownas being operated by motors 262 and 263, respectively. With the mercury switch in the position Wherein the contacts at the left end thereof are closed, these valve motors which are connected in parallel by conductors 265 and 266 are energized as follows: from the line wire |I3 through conductor 245, switch 240, conductor 261, valve motors 26| and 262, and conductors 1210 and. 250 to the line wire ||2. Y

The ow of cooling water into the coils 54, 55, and 56 is controlled primarily by the valves 214, 215, and 216, respectively, thepositionof these valves being controlled by `the proportioning motors 211, 218, and 219, respectively. Thermostats 289, 28|, and` 282 located in the stages 24, 25, and 26, respectively,.control the positions of the motors 211, 218, and 2119, respectively, these thermostats comprising bellows, slider arms and potentiometer resistances similar to the thermostat |40 described above. `Shouldthere bea 10 need A,for cooling in the last stage 26 of the incubator, the thermostat 282 will cause the valve motor 219 to move the valve 216 to open position, theopening of the `valve depending upon the rise in temperature in this stage above the desired value. Water will now )be permitted to circulate through the `coil 56 by the pump 60 by way of pipes 290, 29|, 292, 293, and 2134, the water leaving this coil 56 by way of pipe 295. Connected to the pipe 295 is a pressure responsive device 300 which includes a bellows 30| controlling the position of a mercury switch 302. As the pressure in the pipe 295 increases due to the flow of water through the coil 56 the pressure controller` 306V will move the mercury switch 302 toclosed position and in this position the motor controlling-the valve 305will be energized by way of the .following circuit: from line wire ||2 through conductors 306, 301, 308, switch 302. the motor of valve 305, conductors 309, 3|0, 3| |2|, and |22 tothe line` wire 3. Accordingly the valve 305 will now open and permit the water to ilow through `this valve and into the coil by Way `of the pipe 3|5, `the Water leaving the coil by way of the pipe 3|6 in which is connected a pressure controller 3| 1 similar to the pressure controller 300 in thel pipe 295. This pressure controller will now move the `mercury, switch `321| controlled thereby' to closedposition and close a circuit to. the motorofthe valve V322 which circuit is as follows: from the line wire |2 through conductors 306, ,301,` 323, switch 320, conductor 324, the motor of valve322, conductors 325, Y3|0, 3H, |2|, and |22 to the line wire ||3. The water now Hows through the valve 322 and by way of the lpipe '330.into the coil 54 and leaves the coil by way of the pipe 335 to which is connected a pressure'controller 336 which controls `the positionlof the mercury switch 331 and closes: upon ilowoi' 'water through the pipe 335 to cause the opening of the valve340 by way of the following circuit: from the line wire ||2 through conducr tors,` 306, 34|, switch `331,9conductor 342,` the vmotork of valve V340, conductors 343, 3| I, |2|, and

|22 to the line wire I3. It will accordingly be seen'that upon a call for cooling in the last stage ofthe incubator valve 216'is opened and water "iiows through thecoil 56, causes the opening of valve 305 by the pressure controller 300 whereupon it :Hows through the coil 55 causing theopening of the v alve 322 `by the pressure con` troller 3| 1 whence it iiows through coil 54 and causes valve 2 40 to open by means of the pressure controller 336.`

The water can now flow either through the coil 53 ofthe stage 23 by Way of the pipe 352 or may by-pass' thiscoil by way of the pipe 35| if the valve `350 in this latter pipe should be opened. This valve is controlled by the thermostat 360 responsive to the temperature in the stage 23 `and the motor controlling the position of this valve 350 will be energized whenever the temper- `atureV in the stage 23 drops to apredetermined value, thus causing `the closing of the mercury switch 362 controlled thereby. When this switch closes the motorized valve 350 is energized as follows: from` the line wire 2 through conductor 365, mercury switch 362, conductor 366, valve 359, andconductors 361 and |22 to the line wire I3.)V `'Lhus whenever there is no need for cooling`v infthe stage'23 the valve 350 is open and water by-passes thecoil 53 by way of the pipe 35|. `Shouldthe temperature in the stage 23 however be too high then the valve 350 .willmbe closed and .au of the water must circulate through the coil53 in the stage AGenerally, when it isnecessary to do coolingin the stage -23 it will also vlee necessary todo some'cooling-in the stages "214 and v25 and consequently the flow of water from coil 56 through coils'v 55 and 54 will be desirable.

Then water leaving the coil 53 or by-passed around it may 110W through the coil 310 'inthe condenser |33 by way ofthe pipes 31| and 312 or may by-pass this coil-should-the valve `313 be in open-position. This valve as well as the valve 314 is controlledby the thermostat 315 located in the stage 22. vThe thermostat 31.5 controls a double ended mercury switch -31-3fand when the temperature in the stage 22 -is -suiiciently lowa circuit to the valve 314 vwillbe energizedsas follows: vfrom the line wire ||3 through lconductor 3870, the terminals in the left end of switch 1316, conductor 33|, .valve 31,4, conductorsl 382, 383, and 384m the line wire l| l2. This valve accordingly will permit fluid to flow to 'the coil 5.2. The valve 313 in the bypass around the coil `31|! however will be .deenergized and will .prevent ilow of water through this by-pass. Accordingly the water leaving thestage `23 or flowing around this stage will flow through the .coil310-in'the condenser l|33 where it will beheated thereby and will then flow by waytof pipe 4312 and valve 314 through the coil 52. Atthis time "the valve 433 in the by-pass around the coil 152 will be closed since the :circuit thereto ywill .be interrupted iat the pressure controller 43|. However, should the temrnerature in the stage 22 be suiciently high the valve 31,3 .be energized as follows: from. the line wire lH3 through conf ductor 38E, therighthand terminals .of mercury switch 316, conductor v'4|l8mo,tor fof valve 313, conductors 499, 1453, and .4,02 -to the line `:wire H2. At the same time Zthecircuit through the valve 314 is interrupted 'bythe'mercuryzswitch 316 and this valve will moveto closed position.

' Pressure will now build up in the pipe 312 and the pressure controller40| will tilt the mercury switch 454 `to closedposition .and close a circuit through the valvef4il|l as'follows: from,.the line wire ||2 through conductors 402, 403, switch 404, conductor 405, valve 495, :conductors 4|2, 4|3, and4|4 to the linewire ||,3. Accordingly the water is permitted to by-passthe coil 52 in the stage '22. 4The same mode .of operation will take place Vin the stages :2| yand `'.2||,1the .thermostat 4|5 in stage 2| `,controlling lthe valves 416 and 4H and the thermostat 4|.8 the'stage 20 controlling the valves 423 and 42|. Likewise the valves 422 and 423 in the lay-passes around the coils 53 and 5| willbel controlled by the pressure controllers 424 and 425, respectively. The coils 50 and 5| will receive fluid from the coils 43| and 433, respectively, in the condenser |33 should the valvesv 42| and 4|1be closed, respectively, due to the temperature in thev respective stages being at too low a value. e. e Y It will accordingly .be seen lthatin theilrst three stages of the incubator, namely, stages 20, 2|, and-22 heating vfluid will be'supplied lto the coils 50, l, and 52, respective-ly, by way of the coils 31u, 430, and-43| `in the condenser |33. Wheneverthe temperature many one of these stages rises to the desired valulestheheating fluid will by-pass the. stage and will also by-pass the respective coil in the condenserl33. The water ows backto. the-pump 50 by way of the pipe 62, underlthe control of valve |,|,v the operation of which has been heretofore. completely described. Y

Referring back now tothe stages 23, 24', 25, and

f2Y 26 which will at times require :coolng,1it 'has been stated that thermostat 282 controls the .position of the motor 213 which controls the vposition of the valve 215m accordance with the temperature inthe stage 2li.` In a similar manner ithe valves 215 land 214 control the direct supplyof water from the pump 53 through the stages 25 and 24 in accordance with the temperature in those stages. The motor 4219 which controls the position of valve 213 also controls theposition koi a mercury switch 45|) which controls the ener,- gization of` apump 45|.' Should the temperature in the stage 23 become excessively high Vand valve 216 moved towide open position, theswitch 450 controlled .by the motor 219 will moveV to closed position and energize the Jpump 45| `by way of the kfollowing circuit: Vfrom the line wire ||'3 through conductors |22, |2|, |23, 452, 453, `454, switch i453, conductor 455, pump 45|, conductors 456,451, 458,1 H5', and l5 to theline wire ||2. The pump 45| will now be energized and will cause anincreasein the iioW of cooling water through the cooling coil 56 which will assist in maintainingzthe temperature in this stage at the desired value. .Pumps 459 and 45| are provided for similarly increasing the flow ci water through the coils ,ofV stages 25 and 24. As the temperature in these stagesbecomes high, it will now be seen that the valves 214, 215, and 215 will be controlled in accordance with the temperatures affecting thermostates v28%), 28|, and 282, located in stages 24, 25 and 23, respectively, and whenever the temperature in any one-oi?V these stages becomes excessively' high, or whenever the valves are moved to wide open positions, the pumps associated with therespective stages will be placed in operation to increase the circulation of water through thecooling coils of the respective stages to assist in -reducingthe temperature thereof to the desired value. Check valves 431, 493, and 499 are provided in thefpipes connected to the outlets from'pumps 45|, 455, and 45|, respectively, to prevent back ilow throughthe pumps when they'are not in operation.

There may be times whenv itis knecessary to eect heating inthe stages 23 2|, and 22 while no cooling is required in the stages 24, 25, and 25. If no cooling is required in these latter stages the Avalves 214, VV215 and 216 will be closed and accordingly a pipe '415 is provided between the ,discharge side ofthe pump 6D and the pipe 35|,

and thispipe 415 is provided with a pressure relief .valve416. If thevalves 214, 215, and 215 are all closed, thepressure built up in the pipe 415 by the pump |50 will cause the valve 415 to .open and will permit a circulation of water through that portion of the system` which supplies water to the'coils 50, 5|, 5,2, and 53. If any one of these stages should be calling for a circulation of water through the coils thereof, the valves associated with'those stages will be operated in the manner described above to permit this circulationof water. If cooling should be required in the stages 24, 25, or'25 at a time when no heat isrequired in the rst stages of the incubator, the valves associated, with these rst stages will permit the water to by-.pass the coils therein while at the same time the water is able to flow through the coils associated with the latter stages of the incubator. l

VIt may sometimes happen that the temperature of the outlet end of the'incubator will drop to `a relatively low value, this occurring under normalcircumstances only when there are relatively few or no eggs inthe incubator during the latter 13' stages of incubation such'as` when the incubator is being placed in operation and no eggs have reached the latter stages. At this time the compressor will"be placedV in operation'under the control of the suction pressure controller |56 as heretofore described to `maintain the suction pressure at `a relativelylow vvalue' `butfit should be sufficiently high lso that' freezing of water or heat exchange medium surrounding the evaporator |36 will not take place. During operation of the compressor under this condition the valve |96`is opened asheretoiore described to permit the suppllyofcheating medium tothe heat exchanger |95, thus adding heat to .the evaporator |36 and thereby imposing acooling load thereon so `that longer conipressorv operations will take place before the suction pressure will drop to the cut-ontvalu'e Tand so lth'atmore heat will be given oif by the condenser |33; which heat equivalent is of greater value thanfthe heat delivered to t-he heat CeXchanger |95, and which heat,` in thecondenser 33,VV may jalso be at a higher temperature level,` if the heating medium supplied to the heat exchanger |95 is relatively cool, such as where well waterg'exhaust air piped from outlet 42 to `heatexchangerV |95 through valve |96 or oth'erjlow temperature medium is supplied thereto. "In, this manner, therefrigeration system `will operate even",`i"if thejtemperature at the outletjjen'd of theA incubator drops to a relatively low value so as tosupply `the necessary heat to the incubator duringthe early stages of incubation. i V f Lf As stated above, when thefvalv 24| yisclosed due to the existenceoi a high` temperature inthe incubator, thus causing the water1 to'flow through the coil 255 associatedfWlth theevafporator of the refrigeration systemthe valves 260 and 26`|will be Vopened by the step'contiollenand water,` will be permitted to flowfthrough vthe, coil 480 associated with ,the condenser., of the refrigeration system. Thiswaterwill flow from theupipe293 through pipes 48|, 4182, 4183 into the lower part of the coil 4801and will leave tlie'upper partof the coil through pipes`|i84jand485l `Abranch pipe 486, supplies water"` frommthe upper, ,part of thecoil 480 toa, spray 481flocat`ed in acooling tower 488. Air may flow upwaifdly through this cooling tower to cool the water spray, the air entering through the inletJtiQ` Vand leaving through the outlet opening` 460 in the top of jthe tower. This cooling towenisprovided with" an outlet pipe 49| for preventing the level ofthe water in this tower from rising abovea predetermined value so that if sunicient 4water accumuly lates in the bottom of thecooling tower, it will iiow out through the pipedlltj `A pumpABS is also provided for drawing waterA from the bot, tom of the cooling tower and feedingthis water back to the coil 480 associated` with the condenser |33 by way of pipes 496 and 433so` that when.

this lpump is in operation there willibe a continu'- ous circulation of water from" the cooling tower through the coil 480, thuseffecting a reduction in` temperature of the condenser, `AWhen "the system requires a greater amount ofheating than it does of cooling bythe refrigeration systern, it

willbe undesirable to operate Athe pump 495 since the condenser heat will be needed for" heating the coils 50, 5|, and 52., ljlowever, during,"periods" when the refrigeration system is doing a greater amount of cooling than ,ittis ,o ffuhenating,fthe

temperature of thecon'denser willl'icreasefand this in turnfwill causeanfincrease in the head pressurel Von the compressor" |30.

141 Associated with the outlet of the compressor is a pressureresponsive device 500 which comprises a bellows connected `to the discharge from the compressor by means of pipe 502, the

`bellows controlling the 'position of the mercury switch` 503. Whenever the discharge pressure on the compressor rises suiliciently high, which will be an indication that the refrigeration system is doing an excessive` amount of cooling and that it will be advantageous to cool the condenser, the switch 503 will bettilted to the circuit making position thus causing the energization of the pump 495by means of the following circuit: from l the line wire |14 through conductors505, mercury switch 503, conductor 506, pump 495, and conductor, 501 fto the line wire |13. At this time therefore the pump 495 will be placed into operation and `will cause a circulation of water through the coil 480 `and the cooling tower 488 to thus cause cooling `of the condenser by the coil 480, thereby` reducing the head pressure on the compressor |30. Whenever the heating load onthesystem rises` suilicientlyhowever, sufcient heat will be extracted from the condenser by the coils 310,. 430, yand 43| so that it will be undesirable to ,cool` the condenser by means of the coil,480 and the coolingV tower 488 since all the` heat of vthe condenser will `berequired for heating purposes andthis increase in the heating-load on the system willbe reflected 'by a dropgin the head pressure on the compressor.

In the chamber 38 is a dehumidifying coil 510 through which cooling Amedium `may be supplied toreduce the dew-pointof the air passing thereover and entering the system during times when the humidity of the supply airis excessive. This coil is supplied `with cooling medium by means of a pump 5|5 whichdraws cooling medium from the tank 256 associated :with theevaporator |36 by means ofthe pipe,5l6, the cooling medium then passing throughthe pipe 5|1 to the coil 5|!) and returning-.by way ofthe pipe 52'0 to the tank 256. `The supply of cooling medium to the j coill 5|0 will dependupon the operation of the pump 5|5 and this pump will be operated in accordance with the humidity in the incubator.

For controlling the'pump 5|5, `a humidity responsive device 525 is located within the incubatoror may be located in the exhaust air duct,

" 52Sfwill elongate and thelever 521 will be moved in a counter-clockwise direction byimeans of the biasing spring 528, and upona decrease in hu midity the element 526 will contract and the lever 521 will move `in theoppositedirection. The lever 521 carries a pair of Amercury switches 530 and 53| and'these switches `are so arranged, as will be apparentfrom the drawing, that as the humidity rises' to acertain value the switch 53| wili` be moved to `closed position and as the hu-` midity 4decreases toa predetermined value the switch 530 will'moveto closed position. When `the humidit'yiin the incubator rises sufficiently high that switch 53`|`is closed,` a circuit is established to the" pump V5|5 as follows:" from the line wire ||3 through conductor'535; switch 53|', conductor 536, pump 5|5, and conductors 531 and ||5 tothe unewirei f z; It will thus be seen that when the humidity inthe incubator becomes sufficiently high; that the pumpj5t5 Willoperate to pump cooling medium through thecoil 5|0 which will assegna.

cause. a reduction.. in.u the dew-point.. orthe air enteringthe.incubatorl by. wayiotfthis coil...

Also., located.l within the., chamber 38 i is',v a.. spray 543i which may. b e. supplied. with. water under the. .control of the. valve 54 from a.. supplypipe 54.2.1when the humiditydnlthe 7^incubator becomes suiciently. dow;4 When..th'e humidity, inA the. in-

cubator` drops suicientlm the.. s vvitchv 536V will' move to. closedposition andclose a circuit ,through the-motor con-trolling ,the positionof. valve, 54 I as ffollows; fromfthe line. wire |.I3 .through con.

ductor. 5145,.svv.it`ch4 538; .conductors 54.6, .54.1,` yvalve 54 l; .andyconductors .5.48. and .549.'to the. line wire |.I 2.' Accordingly. thevalve. 54|.'Wi1l; be opened. andthe air.. entering, the. .incubator andpassing cubator is in.. need of .hurnidi fic.ationwhich .will

generally be1 at` times ,when the outside air. is Y.at arelatively lowtemperature, this air. may. have its.temperature. increased b'y the eoi1.5.5 2l sothat it will b eableto absorb; additional moisturefrom the spray.I 5481.. and.v this coil.j5.52 .receives water.

from thev pipe, 48| andthe pipe..555 and the Water is .returned .to vthe 'pipe .485 -from -the c oil .552 by way of the pipe, 55.6; Theflow of -water l`togthe,

coil 55.2"is un der the controlioa valve 568 which is normally. closed" andJ opened only when the valve; 54|` to the spray 546`isopened indicating a need of f humidication. Itjwill' be notedf from anexamination ofFi'gure-'Z `that the valve 560 is-connected to theliile'vviresv ||2 and I |3'through thfeLsw-itch 530inparalle`l'with'the valve 54| by means ofi-'conductors' 56|"andf562 andv it will accordingly 'be apparent `that the `valves* 54|v and ilfvvill `b'e simultaneously opened' and closed;

' The bottom'off'the chamber38fis' providdwith a. sumprto'.receivefwater'from" the spray 548i and this vsurnpiis.L provided `withPa-pair of outlets 565 and:A 586i whiclrzleadto; the'fspray 561" and the chamber: 38--through the: pipe.y 565-: The air-leavingf the= incubator, passes downwardly .I through the;- chamber` 4|! oven the i heat '."exchanger 40; as hasibeen. pointed out above,y andfbefore.this

passes. outwardly-through.v the opening 42 it must passover.. the .sprayfpipe561cwhich spray. will be rather cold under normal conditions since the spray... 54.0,is.,only operatingt those. times. rwhen there is aneedforfhumidiication whichwil-l more otenzoccurlin coldweather. The air leaving the: incubator givesfup. agreaten portionof. itsv ,heat f tothe. ain. entering... the.- -incubator by.. means of thef-heat., exclfiangery 46.. but.. this, air may still be considerably. above. the temperature of. ,the spray@ 5.61 and ,accordinglwthefspray 561 will...be able..to.

extract a.. large... amountI vof, heat.. from .the out.

going.; air, andthereby bewarined.. This .water'f which has, now. been :warmed by. the; outgoing air flows .by ,way .ofa pipe. 516 intothe ,coil .36 which is located `in .the chamber. 35.2 and. is providedifor further 'preheatir-ig. the airrenteringy .the incubatory the .-water.v leaving,this.` coiliby wayf'ofil pipe 511 and. passingfin'tofthe I chamber 488,' thus;4 forming' an additional-- supply.- off vvatenv zfory theY cooling Waterleavingthe coil 3.6. If 'the .outsidey tempera tower 488; It .wil'laccor-dingly; beseen thatwhilef the-outgoing air. gives; upba large'.Y portion of itsheat to Vthe air.entering..the.incubator byway of the. heat. exchangerf 40, frulitheuheatis extracted: f .this airf. andgiyen to,.- thetincoming. air. by..

means .cf .thc-.Sprayv 5.6.1"and the` preheatnacqil. 3.6i) In 0f EL' weather, thel water iibwingtothe, spray 568'vvill 'be .about "60'F-'ani1the water4 dowing through pipe 5.115 to the coilj36 Awill` vbe about '759 F.

The valve 51.6.lwhich1controlsthe How, ogjwater to. thespray. 568 is controlled 'bythethermostat 580 which comprises ab'ulb 58j locatedir'i.contact with the pip,el511,` this Vbulb being` connectedby means .of a `capillary tube .582 with. a bellows. 583g; this bellows. controlling the. p ositionoffa slider arm 585.which.moves,over a potentiometer .re sistance .586' in accordance withvariations inthe temperature of .the Water flowing; throughthe; pipe. 511.. The slider. arm. and. potentiometer form a. control means for-the, motor `tjwhich;A

i controls the position. of thejvalve 5111,.this.motorV being aI proportioningmotor of. thetypc described above so that vthe position o ffth'e` valve. .510.;Wi11'. Vary in accordance with the .tempcratureictthe ature isexcessively lowandf'alarge amountof water must beadded .to this, air for humidicaf. tion purposes.. itlmay. beA necessary. to futthei. raise the temperature of the. airpassingrto the. spray. 540 so thatwhen the .temperatureoffthe Water leaving. thecoil 36'drops, the valve. 5.18.; will. begin .to open. permittingwater to flow .from the spray 568 tofurther raise...thetemperature of the air and'increase the amount of .'moisti1r absorbed .therebyin the first Stage..

Should. the supply.y of` water to. the. cooling' tower 488 by way ofthe pipe 511 be` insuiiicient.;

. ofthe pipe 605 whichccnducts this water-intcx the. sumpn inA theV bottom of; 'the chamber 38j.

Iffthe, temperature ci the. air entering;y the.. cooling. .tower 488 is excessively low, the air. in chamber 4| vleaving the outlet42 may bebenducted to theinlet 4,895 of the coolillgjtower 488, since this airwill alwaysA be ata relatvelyhigh, value such as 50? F., 4 or to the evaporatorchamgber 256 through control valve |96, to,.heate.x changer |95..

Referring ,now toFi'gure 3; the4 means forcausf. ingautomatic ejection of sterile, eggs ,ata are; determined time during, their passage, tl'iroughA- the incubator will lbe explained. This egg .ejecti-` ins. means is. preicrably. located. ata. pcintwhich. the eggs will reachshortlyaftei; theirvthirdgiday in the. incubator. andi'thisv means: includes. are. rangement utilizing @them-electric cellfcr. other; such device, for determiningthe. fertility. OIT the. eggs. Locatedabcve, the incubator. is a series ofi Suitable lights... or. other. energy radiatingelec..- tronic: devices.v 6.59,. .there beine .one light. Q1'. de: ViCe-fOreach. 110W 0f figg. CQmPaImelllS Omthf beltJ I although` for, purposes .of 'illustration only... one has been illustrated; and1on.thecpp.osite side. ofi` the belt is a photo:electric.c ell.A 65|;or other radiant. energyl sensitive.` device. Lenses.` 652 .and 6.53, .or the,like,are located on opposite., sides. of; the belt.. and., between.. the lights,Y or. radiating means, 656; andi, the photo-.elfiltric 17 cells. or radiant energy sensitive means, 65|, to direct the rays from the source to the sensitive means as shown by dotted linesin Figure 3. When light or other rays pass from the source 650 to the photo-electric cell, or other ray sensitive means, 65|, current is supplied to the amplier 655 in a manner well understood in the art and this amplier supplies current to a solel noid 656 at such times, the supply of current to the solenoid also being under the control of a timer 660. This timer comprises a cam 66| carrying a plurality of projections 662 thereon, this cam being connected for rotation with a sprocket 663 over which the conveyor belt passes so that movement of the cam 66| is initimed relation with the movement of the conveyor belt.

eggs carried by the belt are in a position to intercept the beam of light or other radiation between the source 650 and the photo-electric cell, or other ray sensitive means, 65|. If the egg is fertile it will permit the passageof relatively little of the radiant `energy used therethrough after the third day of incubation because ofthe embryo chick therein. Should .the egg be sterile, however, sufficient radiant energy will pass through the egg so` that Wthe radiant energy sensitive device will cause the energization of the solenoid 656. l

Referring now to Figure 5 wherein is illustrated a` fragmentary portion of the conveyor belt, the conveyor belt comprises a pair of sprocket chains 610 on either` side thereof, only one of such chains being shown. The sprocket chains comprise a plurality of "interconnected links as is conventionalandisome of the pivots 61| for these links are extended as rods 612 so that the two sprocket chains are interconnected by means of a series of these rods. Rotatably carried by these rods as by means oi.' the rings Atransmitting material such `as a foraminous screen, these supporting members being biased upwardly by means of the springs `616 into the plane of the belt. i The supporting members may be limited in their upward movement `by engagement of the spring 616`iwith the wall member 680 described below, or in any other suitable manner. Suitably carried by the rods 612 are the partitions I5, shown in Figure 5 as extending between the wall members 680, which together with the supporting members 615 form separate compartments on the conveyor belt which separate each egg on the belt from the other eggs thereon. The wall members at one edge of the belt may be U-shaped as shown in Figure 5 thus surrounding three sides of the `egg and this U-shaped member cooperates with the next U-shaped member to form the fourth side of the compartment asclearly shown in Figure 5. The remaining compartments widthwise of the belt may beformed simply as L-shaped members 682, each L-shaped member cooperating with a similar member for another compartment to form the four upstanding walls of the compartment and in this manner each egg is separated from every other egg on the lbelt by these upstanding wall portions so that as air is circulated upwardly through the belt, no two eggs `being carried thereby will be contacted by the same portion of air. These upstanding wall portions are carried by the rods 612 independently of the supporting screens 619 so that movement of these screens around the rods 612 as an axis `against the force of `the biasing springs 616 is permitted.

` Each of the screen members 615 supporting the eggs has suitably supported adjacent its pivot and on the underside amember 685 which may be made of soft iron for example and will be attracted by the armature 686 of the electromagnet 656 when the magnet is energized. Upon energization of the magnet, the soft iron pieces 685 will be attracted to the armature 686 thus causing the screens 615 to pivot ldownwardly and permitting the eggs to roll out of the belt Il.

Supported below the belt is a guideway I9 suitably located so that when the supporting members 615 are pivoted i downwardly under the in- Vfluence of the electromagnet 656 the eggs will roll into this runway I9 and will roll out of the incubator wherethey maybe gathered and disposed of as desired. i w

It will now be seen that at predetermined intervals the switch arm 665 will be moved into engagementrwith the contact 666, it being understood that there is a separate switch arm and contact similarly operated for each rowlof egg compartments on the belt 'and'if the light from the light source 650 passes through'the respective eggs on thebelt, which will happen only if the eggs are sterile, current will ow through the respective amplifiers 655 through the electromagnet 656 by means of` conductors 610, switch arms 6615, con-Y tact 666, conductor61l, coil 656 and conductor 612 to the amplifier 655, power being supplied to the amplier by means of line wires 695 and 696 connected to any suitable source of power (not shown). If this circuit were not interrupted periodically by the timer'660 `the light would pass from the source 650 to the photo-electric cell 65| when that portionoi the belt directly back of theegg were between the light source and the A photo-electric cell since the egg compartments are made somewhat bigger than the eggs and this would cause downward movement oi the floors of the compartments.` It `will thus `be seen that' whenever a'sterile egg moves into `the path of the light beam from the light source 650, the egg will be` automaticallyejectedfrom the incubator so that no` sterile eggs will move through the incubator after the third-day, for example. Obviously, rays other thanlight, and ray sensitive means other `than photo-electric cells, may `be used, as previously described.

Attention is now ydirected to Figure 6 which shows one suitable form of belt cleaner and purifier 21 through which the belt passes after leaving theincubator so that the portion of the belt entering the incubator is always maintained in a clean and pure condition. The belt passes from the exit endof the incubator into a tank containing a supply of cleansing and sterilizing fluid 10|, this fluid being continually changed by means of a pump 102. The iluid from the tank 1010 flows through apipe '|03 into areceptacle 104 having its top portion in communication with the pump `inlet by means of` a pipe 105. Aiscreen 106 is `pump 102. The pump discharges the fluidi which has now been relieved' of 'its' dirt particles into a puriiier 1,1!"5` which may be lof any suitable :con-v struction andmayftake the iorm of .ran'ozoneigenerator `through Ywhich power :is supplied icy line Wires :1B-1 and 1:68 the-fluid being-'completelypurifiediin the purifer 106 :andreturningfby means of the pipe Misinto the 'tank 1,00, :Thisiarrangement thus continuously :changes Athe ifluidi-n the tank .1160, removing dirt'th'erefrom fandpurifafing it so that a completelyrsterilized cleaning vfluid is continuouslysupplied tothis tank.l v,'IhereCep- .tacl-e 1-04 may be provided Awith a clean-out door 'H2 so that accumulated dirt on the-screen'l may Ebe periodically/removed,'there being a shutoff valve 1:1?.5 in the pipe 103 lso that :theilow' of duid into tthe :receptacle 104 may be shutoff at such time.

Locatedabove :ahorizonta'l runof the'be'lt 1 Il fis .abeater Y'120 vof any suitable constructionfandmay be :provided with vsuitable flexible beating memf bers 1.2Iiwhich maybe formed of leathergor'other suitable material, the beater 12D: being .connected 'by` meansoi thebelt T22 to .a motor 1:23 'to 4cause rotation-of the same. The, beatingeelements l2! cause ia continual beating vaction on 'the :back: of the .belt vl I so that Aany loose foreign matterzsuch as egg shells or the like will be removedand fall Aintoa guide '125 Whence'they'will passvintoa suiti:

able receptacle '126.V In this manner :the 4belt is removed of -.the majority of foreign matter :prior .to entering the cleaning receptacle 100;. 'The -motor 1.23 also drives :by means of the belt 1:2.8 a brush 'lr-3 i)v 'having suitable `bristles for engaging the back of .the belt *l-I iin 4the 'tank 1:00, thus imparting a scrubbing action tothe belt "and completely 'removing :all :remaining foreign matter Y 'therefrom and :since the liquid within the :receptacle '100 is continually cleansed-iandi'sterilized 'it -will be apparent that the belt las it :leaves the receptacle will `be `in a cleanean'd puried condi'- tion. To lsummarize briey'theroperation of rthessystern of Figures 1and1'2,:itwill be seen that la supply of fresh vair is being continually .circulated through theincubator although this supply may be relatively small, the air 'flowing upwardly C.

`around the heating or cooling coils, v:through :the porous walls, passing through the conveyor lbelt and passing outwardly ifrom the incubator through the upper porous `wall thereof, this circulation of fair 'being effected by theffan '33. The .i

walls iof the incubator are kept `at `desired'temperatures in the various stages andfin this man# ner the Aeggs on the -belt 1H rwillbe-malntained `at desired temperatures,` which might .'be- 100 .'F,

in the first 'six stages of incubation and '98 F. 5

inthe last vstage of .incubation or the :hatching stage. Since in `some :stages :of incubation ythe eggs will require heatinforder to maintain them at:the proper temperature and Asince inthe latter stages the eggs will'be :generating .a'large amount of heat, it will bene'cessary `to Yremove :some .of -this :heat in these :latter stages. `The lheat "given up bythe 'eggs inthe Alatter:stageslof .incubation is conducted to the :rst stages of Aincubation iby means of the `water circulating through ythe-various coils imbeddedin the wallsofnthe incubator.

r'Ehe pump G causes'waterjto circulate'through the vdesired -coils, :the Vflow-:of water .to pump :being controlled by the valveB|, `and this -valyet's operated to circulate a: sucient-amountfof -water :so thatgthe lwater passing to ithe-pumpfwillibe lmaintained atia desired :temperature-Which tem- ;perature will be variable 'depending upon `the number -of :eggs `in the incubator andtheftem- Cil ' `fperaturer-ofthe .space -in which the incubator is t5 located. lher:mostats :in vthe various stages lof the: incubator control :the .supply :of water itorlthose stages 1in a `manner tof-maintain :the temperature .therein at the-proper values and when zthefincu b atorl temperature rises fsuiiciently hi-gh, vind-ica-ting -a need `tor-:considerable .cooling in the llat.- ter stages tof ,incubation the'cooling uid'is cooled by :circulating this water lin heat :exchange `relationship :with the evaporator of :a refrigeration systernby closingthe valve 2:41 :in the iley-pass to the coil-` 255. The :water -for heating the coils: in the;'early:stagesl ci :incubation is heated :bl/passing `through 'coils `which are in :heat exchange lrelationship with the, :condenserjof the ,refrigeration system :shouldheat be necessary .inthe earlystagesof incubation, Since the-water transfers-:fthe heat :romthe incubator ,in the` llatter ,stages of- Vincubation Vto the earlystages'ofpfn- .cubation,: it v:will normallybe unnecessary :to iur ther 'cool or heat-the water-*to any considerable extent and itis therefore possible 'to utilizexa refrigeration :system of :relatively small capacity for supplying the necessary 4heating and cooling to :the Vvariouscoils inthe incubator.V

The kva-riousfheait-exchangers:by -whichithe heat ofthe'outgoing air `is given 1up, Nto the incoming fai-rrf-urther `increases the operating eiliciency` of the systemand yarlarge partof -the available sensible Yand laten-t heat .leaving `-the :incubator vis 'impartedvto the rair entering the same.

The cooling tower 483 operates `to cool rthe :condenser |33 duringperiods when nthe Arefrigeration. system is Abeing :utilized to efectalarger amount of lcooling than lieat'irur-andfin ftnese instances the head V:pressure on th'e .compressor will increase and the pressure soonltroller llwill 4operate the "pump 495 `to circulate cooling fluid through the cooling tower 488 and :the cooling coil ilt, :the valves 1260 :and 26:1 being y'openyat `,this time by' the :step::control1erA I:4-I" whchxcaiises these valves to iopenwhen suioienticooling; :o

ithedatter-:stages'zof the incubator :is necessary.

v.The compressor l 3i): is control-led thy therswiitch tlf5| of the :stepccontroller VMl Il insuch-a manner thati 'when `.the temperature `adjacent the outlet ofthe-:incubator isfabovef98 5F., for example, the fcornpressorroperates ,to :maintain 1a suctionv pres:- -sure-,offO lbs., ffor example. Between95 and 9.8 :F. the :switch lliel will be in open circuit; Iposition `andthe.compressor v.will be shut tdown. :Should the temperature :at :the controller l-.'i'dropftoefa still ,lower 'ivalue such `:as 95"J thefcompr-.essor v.will :operate to` :maintain .a lowersuction :pressuresandf :at: ,the same time heat :willheisllpllled by the exchanger Ij9,5to the evaporator I-3 B f'thus .loading the :compressor so. thatsufllcientiheat will 'bef generated :1in the :condenser .1f-33 to produce .thefnecessary'heatjor the early stages vfof incu- `ba'tion, -i-t being :understood .these conditions will fnot occur :underV normal circumstances but fonly 'whenthere :arev relatively -few for no :eggs Qnfthe belt Min @the flatter stages4 of incubation;

4(During:periods"when fd'enumidi'cation-v ci the iairpassingatothe incubatorfis :necessaryiley `rea- `:son fof the :humidity `within 1the-incubatorv-rising too high, the- -humidity responsive Vvdevice-152% fcausespump el 5 toscirculate fluidfrom :the .Coolchamber .1256 :through zthezcol :5LB-@to :reduce tfhe ,dewegpoint of wthe-air entering thefincubator. IiIf on the :other fhand ithef yhumidity .in the 1in- 4cubator :falls too flowgvalves 1541 :and T550 zaregoph., thesprayn is 'operated and the; :tempering coil 25,52 is,.supp1ied-with -water to temper 'the :air passing :throughfithe'zsprayfe whereby-ftheitempera-ture of therair. svi-l1 befraisedfand more'water may be picked up thereby. The water from this spray 540 is utilized to absorb latent heat from the outgoing air in the chamber 4| and transform this latent heat into sensible heat of the incoming air passing through the chamber 35 by means of the coil 36. In excessively cold weather the water leaving the coil 36 may have a Very low temperature and the spray 568 is at this time operated by the opening of the valve 510 to increase the humidity of the air passing into the incubator.

The eggs are automatically ejected by means of the egg ejector |8 at a predetermined time during their passage through the incubator if they are in a'sterile condition so that they may be collected and used for a useful purpose such as the manufacture of egg powder before they have been in the incubator for too long a time. The cleaner 21 maintains the belt in a clean and sterilized condition thus materially reducing spread of germs to the eggs on the belt.

It will thus be seen that I have provided a system for controlling proper conditions of temperature and humidity in an incubator of relatively large capacity by the use `of a relatively small refrigeration system for supplying whatever heating or cooling is necessary to the incubator and the employment of such a small system is made possible by a very efficient arrangement for ,utilizing the heat released by `the eggs in the latter stages of incubation for heating the eggs in the earlier stages of incubation and under many conditions very little heat or cooling will be required by the refrigeration system since the heat given up by the eggs in the latter stages of incubation may be all that is necessary to properly heat the eggs in the earlier stages. Since the air which passes through the incubator flows upwardly through the belt and since the eggs carried by the belt are all separated by partitions from one another, the air in the incubator is maintained in a condition of purity at all times and the circulation of air is unable ito spread any germs` that may be on or in one eggtoanother egg since there is noportion of the air that contacts more than a single egg.` The employment of other means such as chemicals to reduce the germ concentration of air in the incubator is `rendered unnecessary by this arrangement and `since. the use ofV such chemicals reduces the number of chicks that are hatched for a given number of eggs, the losses from unhatched eggs are Vconsiderably reduced and are also considerably reduced by reason of the fact that the temperature and humidity of the air in the incubator will be maintained at the desired value at all times.

Referring now to Figure 7, I have illustrated an incubator with a simplified form of air conditioning system, this'modication being suitable for smaller units. Although embodying the principles of the system shown in Figures 1 and 2, the present modification involves the use of relatively little pumping and control equipment, thereby permitting a reduction in cost and maintenance, at a slight sacrifice in flexibility. It will be `noted that the undulating egg carrying chain, the egg ejecting mechanism, the chain cleaning structure and the general principles of the heating, cooling and Ventilating of the eggs, are the same in this modillcation as in the one previously described.

but use is taken of the heat absorbed by the 'cooling fluid circulating through the coils in the lat,

i 'ter stages of incubation for supplying the heat to the incubator in the earlier stages of incubation as in Figures 1 and 2. A-pump 880 is provided for circulating the fluid through the various heat exchanger coils embedded in walls of the. incubator, there being a cooler 80| located between thepump discharge and the coil in the last stage of the incubator whereby cooling of the heat exchanger medium may be effected if required. A heater is also provided between the coils 52 and 53 in stages 22 and 23 so that if insuiicient heat is absorbed by the cooling medium in the latter stages of incubation to raise the temperature at the opposite end of the incubator to the required value, this may be done by the heater 805.

A cooling mediumis supplied to the cooler 80| by means of a pipe806 under the control of a valve 801 which may be operated by any suitable means such as a solenoid 808, the energization of which is controlled by a thermostat 8|0 which respondsto the temperature adjacent the outlet end of the incubator. This thermostat may be of any suitable construction and for purposes of illustration is shown as including a bimetallic element 8|| controlling the position of an arm SI2 with respect to a fixed contact 8|3. When the temperature at the thermostat rises to an excessive Value, the arm 8|2 moves into engagement with contact 8|3 and energizes the solenoid 808 by means of the following circuit: from line wire 8|5, contact 8|3, arm 8|2, bimetallic element 8| I, conductor 8|6, solenoid 808, and line wire 8H. Thus whenever the temperature adjacent the outlet of the incubator becomes excessive, the valve 801 is opened, cooling medium is supplied to the cooler whereby the heat exchanger medium being. circulated therethroughA by the pump 800 is cooled whereby additional heat may be absorbed from the incubator to reduce the temperature in the latter stages to the desired value. l

Any suitable heating medium may be supplied to the heater 805 under control of a valve 820 the position of which may be controlled by a solenoid 82| which is under the control of a thermostat 822 located in the inlet end of the incubator, which is shown to be similar to the thermostat 8|0, the arrangement being such that when the temperature adjacent the inlet of the incubator drops to a predetermined value the thermostat 822 closes a circuit through the arm 823 and contact 824 thus energizing the solenoid 82| as follows: from line wire 825 through conductors `826, 821, thermostat 822, arm 823, contact 824,

conductor 830, solenoid 82|, and conductor 83| to the line wire 832. Accordingly, whenever the temperature adjacent the inlet of the incubator drops to a low value indicating that insufficient heat is being absorbed by the heat exchanger medium in the latter stages of incubation to raise the temperature in the early stages of incubation to the desired value, `heating medium is supplied to the heater 805 so that sufcient heat will be radiated by the heating coils in the earlier stages of incubation to raise the temperature therein to the desired value. Under normal conditions however, if the incubator is properly insulated and is substantially full oi eggs, sufcient heat `may be absorbed by the heat exchanger medium in the latter stages of incubation and added to the incubator in the earlier stages 'of incubation to maintain temperature in all parts assortie thereof V atapproxmateiy the-.desiredfvalues- The temperature of the, fluid. being. circulated will normally not; fluctuate more than. about two de..- greesfthroughout the cycle;

The heating .and cooling requirements of each stage are considerably different. from every other stage., For example, the:v -rst .stagetake about` 80% of the heat and the last stage may take about 7.0% of the cooling.. The intermedi ate. stages Will require. Varying amounts. of heat.- ingv orcooling but veryn little of: each.. order tocarry thev heat. absorbed in the last. stage to the first. stage. without losing. iton the Way,..it. is desirable in mediumsized incubator-'sto propere tion the heat transfer surface in each stage Vto theA load in the respective stage. Thus, the rlast or hatching stage have about. '70%.v ci', the surface in the total of the lastA three; stagesand the irst stage may have. about 802% of? the surface in the total of the rst. three. stages. With this arrangement, Water, if used as the heat transter fluid, may leave thlast stage ati about 102' F. andl enter the first stage. at. about 1111.5.'Q F., as there is so little heat transfer between theseY stages, and. thewater may leave. .the first stage Aat about916ff F. The amount .of heat radi..- ating and absorbing surface in each.. stage will thus vary considerably* in proportion to the amount. of. heating and cooling. to, be, done and the temperatureV ditlerential. required, based:r on a norma-l percentage (say 85 of a. furl-l1 load of eggs in the incubator being fertile.v

Located within the incubator atza suitable loca.- ti'on, such as adjacent the centerportionthereoi is a humidity responsivezelement, 8353 of; any suits able construction. andwhich controls; the position of an arm 8%v with respect.- to a pair of xed contacts' 83T and 83= in responseto the humidity existing within the incubator. When the. humide ity in the incubator is` excessive. the. arm: 8&6 eng-age the contact 83'lfandqif. the humidityv drops tov an undesirab-ly low Value the. arm 83E will engage the contact 83181. When thefhumidity is at the desired value however', the arm 83%wil'l be between the contacts 3:311 and 833i and engagement with. neither Contact., This lhumidity responsive devioecontrols the ope-ration of: a. pair of. valves- Sdil and 8M., the positions' of: which may loe-controlled by solenods .8d2 andll, re.,- spectively. rThel valvel 840 may control'the supply of=y a b-umidifying medium.. to. the spray BM Whereas. the. valve 8MS may.. control .the supply ofa dehumidifying medium` tothe spray 845. Both.v of these sprays:y are arranged in: the. path of fresh air entering the; incubator, this pret'- erably passingthrougtr a heat exchanger 4l] simi- 1arte-that shown. in Figure. i fortempering. the air prior to passing into. the. incubator;

Iii the humidity in the incubator too; low, l

arm 836. will engage contact. 83.8` .thus energia.- ingfsolenoid M2` as follows: from. the limewire S25-through conductors 8:26, $510; arm 83.6, con..- tactV 838; conductor 8551, Vsolenoid 842: and .conduce tors 85| and 852 to the Aline Wire 332. Energization of the solenoid. causeso'pening ofthe valve wide accurate control of. temperature ineach of the stages. of the incubator nevertheless. it does embody the. principles. of the. system of 1 and 2 and does provide control ofthe: tempera,- ture adjacent the inlet and outlet of the..incuba-A tor and of the humidity Within the incubator and such a system may' provide suiciently good. con.- trol forv inoubators ot small capacity,.org average fullgload. fertile eggcapacity.. This arrangement willtalso be suitable for inoubators of large: ca, pacity but .since it. does not: give asaccurate: con: tro'li as.V the .system of Figure 1,. there may bea greaterloss oi ohicksfrom. fertile eggs. .than with a: system of! the type shown in Figure; 1;. The amount of.. control necessary' wifllaalso vary: some1-.- what in accordance with climatic `conditions in the; section of the country in Whichthefin'cubator Aisy to be used, and the proportionate amount.- .0f heat. transfer surfaces1 till; 5 1', 52.', 53.4, etc., must also be varied to suit.- such: prevailing. .different surrounding climatic.v or temperature conditions.

Any suitable. dehumidifying medium may be employed in4 the spray iand this mayftake the form iffdesired or. a. solution ofV calcium chloride, which. mayalso be` utilized in system oflig.-v ure lf if desired. The unitB-.ofxFi'gure 1 may also be replaced if desired by a lump calciumdehumid.- incr-for very. humid climates.-

Having described .two preferred iormsiof my invention, it V.will beapparent that-manymodica.- tions may be made by. those skilledin. thegart'and I therefore Wish. it. to. be understood-that invention is. limited only by they scope. of the apt pended claims. y

I.v claim asrmyinventionc 1. eggA incubator comprising a'. conditioned space, means for' transferring. eggs through the conditioned space, said means comprising an un.- dulatlng belthaving a plurality of. transverse rows oi individualegg compartments, eachof said rows of compartments being articulated to the adjacent-rows, means for' circulating. freshair. through the-conditioned space, and. meansifor. preventing any.y portionv ofthe: air being cireulatedvthrough the conditioned 'space lfrom.contacting more-.than

one* egg..

2. In.astructure.housingrobjects:requiringzheat in onev locatonanld.. requiring cooling in .another location, said objects. requiringy ventilation; by freshainfheated Wall surface means; for heating said obj ects in saidone. location; cooledaWai-Lsurf faces. for cooling said objects in. said; other `1ocation, means transferring: heatl absorbed ley-said cooled Wall surfacesto said `heated Wall. surface means, and' Ventilation. means, saida Ventilation Vmeanscomprising.'heat exchange-rneansior'transr ferring heatV from: air' exhausted from'said struc.- ture. to the fresh air bengj supplied, `said `iresh air moving .through saidwall surfacesztrans.-

versellyl of saidr structure.

3?.. An egg incubator havingy porous upper and l'ower Walls, heatexchanging. meansinsaid` means. tor conveying eggs Athrough the incubator, means for circulating. a heat exchangingmedium through Vthe heat. exchanging means, the heat ex.- changing medium absorbing.heatliberatedby the eggs during --the .latter stages of. incubationbylradiation andheating the. eggs during. the: .early stages of incubation. by radiation, and;

25- responsive to the temperatures in various portions of the incubator for controlling the flow of the heat exchanging mediumthrough the heat exchanging means in the respective portions thereof.

4. An egg incubator having porous upper and lower walls, heat exchanging means in said walls, means for conveying eggs through the incubator,` means for circulating a heat exchanging medium through the heat exchanging means, the heat exchanging medium absorbing heat liberated by the eggs during the latter stages of incubation and heating the eggs during the early stages of incubation by radiation, and means for causing a ii'ow of fresh air into the incubator through one of the porous walls thereof and around the heat exchanging means and withdrawing the air through another porous wall and discharging the air from the incubator.

5. An egg incubator comprising a conditioned space, means fortransferring eggs through the conditioned space at such a rate that the eggs will be hatched a short time before the eggs leave the incubator, means for testing the eggs for fertility during their passage through the incubator, and means for automatically ejecting those eggs which are not fertile from the incubator.

6. An egg incubator comprising a conditioned space, means for transferring eggs through the conditioned space at such a rate that the eggs will be hatched a short time before the eggs leave the incubator, an electronic source past which the eggs pass during their passage through the incubator at a predetermined-time, and means responsive to the passage of a predetermined flow` of electrons from vthe electronic source through any egg for causing the removal of said egg from the incubator.

7. An egg incubator comprising an incubating chamber, `a belt for transporting eggs through said chamber at such a rate that the eggs `Willbe hatched by the time they leave the chamber said belt being constructed of a plurality of supporting sections each of which may bepivoted downwardly to permit the egg supported thereby to drop from the belt, a light source past which the eggs pass on their way through the incubator, means responsive to the passage of light of predetermined intensity from the light source through any egg to cause the supporting section therefor to pivot downwardly, and means for guiding the eggs released from the belt to the exterior of the incubator.

8. An egg incubator comprising an incubating chamber, a belt for transporting eggs through said chamber at such a rate that the eggs will be hatched by the time they leave the chamber, said belt being divided into a plurality of compartments separated from one another by nonporous walls, each of said compartments being designed to support a single egg, the bottoms of the compartments being composed of porous material, and means for causing a flow of conditioned air through said incubator, upwardly through said belt and past the eggs carried thereby and eX- hausting the air from the incubator after the air has passed over the eggs, the non-porous walls forming the sides of the compartments preventing any portion of the air from contacting more than a single egg.

9. An egg incubator comprising an incubating chamber, a belt for transporting eggs through said chamber at such a rate that the eggs will be hatched by the time they leave the chamber, said vbelt being divided into a plurality of compartair has passed over the eggs, the non-porous walls forming the sides of the compartments preventing any portion of the air from contacting more than a single egg and means for continuously cleaning and purifying the belt subsequent to the hatching of the eggs thereon.

1D.` In` an incubator, an incubating chamber, an endless belt having a portion thereof passing through the chamber for transporting eggs therethrough, means for maintaining proper conditions of temperature and humidity throughout the various portions of the incubator, means for causing a continuous circulation of fresh conditioned air upwardly through the belt and past the eggs for maintaining the air surrounding the eggs in a pure condition, meansfor automatically causing the removal of nonfertile eggs from the` belt and incubator after `through the yincubator for transporting eggs therethrough, heat exchanger coils `in the porous walls of the incubator, means for causing a flow of heat exchanging medium through said coil's for absorbing heat from the eggsduring the latter stages of incubation and imparting heat to the eggs by radiation during the early stages of incubation, means responsive to the temperatures in various portions of the incubator for` controlling the ow of the heat exchanging nie` dium in said portions thereof, means for causing a flow of fresh air around said heat exchanger coils in the lower wall of the incubator, upwardly through said belt and past the eggs thereon and withdrawing the air from the incubator through the upper wall thereof,`means for passing the air leaving the incubator in heat exchange rela-V tionship with the fresh incoming air, means for testing the eggs at a predetermined point during their passage through the incubator, and means operated thereby for causing the sterile eggs to be removed from the incubator.'

12. An egg incubator having porous upper and lower walls, heat exchanging means in said walls, a porous belt having a portion thereof extending through the incubator for transporting eggs therethrough, heat exchanger coils in the porous wall of the incubatormeans for causing a ow of heat exchanging medium through said coils for absorbing heat from the eggs during the latter stages of incubation and imparting heat to the eggs by radiation during the early stages of incubation, means responsive to the temperatures in various portions of the incubator for controlling the ilow of the heat exchanging medium in said portions thereof, meansm for causing a iiow of fresh air around said heat exchanger coils in the lower wall of the incubator, upwardly through said belt and past the eggs thereon and withdrawing the air from the incubator through the upper wall thereof, means for passing the air leaving the incubator in heat sterile eggs to .he :removed `.from .the fi-.riouloetorl a. densa-hs Carried byfsaidbeltor 41J.reventiiisl ,-.pcrtion 4of the airiiowing through-theme11- bator 'from Contacting more :than i orio. -v osg- 11.3. .ln an egg. incubator, :means l.for transportihgieggs, therethrough, a light source adjacent '.to the path of the eggs through the. incubator', a photo electric. .cell .freoeivinglight from thelight source, :the-iphotO-.eleotrio .coll being .fso .arranged with respect -to the lig-ht sourcesthat the :eggs move across. the-pathof '1lightrto .-thepphoto-.eleotric.. cell, and means. operatedv by` the photo-electricoell Whenit receives sufficient lightf-rom'the light source for causing removal vof the egg ,per-Y mitting thetransmission .of .lig-htifromithentransportingfmeans.

1%. `I En an egg.meubatorL a light .transmitting eoiweyonmeansrfor .conveyingoggs `through the incubator, said .conveyor .means :being .divided into .separate .ogg :carrying sections, :each .offsaid sections lhaving .a fdownwardly vtiltalole .supporting gmember, a light source on @one .Side of said conveyor means, a photogelectric cell ,Onthe opposite `sicle of said conveyor means vand disposed. totreceive V light therefrom unless L,the lightis ;in terceptedA by an egg, means .operated by said photoeelectric cellwhen it receives sufficient light fronigsaid .light source for causing `said-.snppcnjtiiigmember to be tiltedtdownwardly, andiiheans intermittently rendering said photo-.electric .cell

inoperative Lto .cause .downward Itiliihlg of. the f sapiiortihg .momberso -thatif .an ...egg ,is on the siigporting member, .the photo-electric cell .will b eqperativeonly Whenthelight from,the light source .must pass through .the egg tov reach the photo-electric cell.

Z1,5. In lan incubator having an elongated passage. means for progressively advancing eggs Ythrough :said passage :in lsuch `manner `.that eggsintroducedv atc one vend y will be. hatched .the time theother end is reached, heat exchange y,means for-'tempering the lair in said passage, :means circglating a heat exchange medium through-said heat exchange means, .means ,for heating Isaid medium, means for cooling said medium, .temperature v'responsive vmeans near said one end ff or controlling saidheatingf means, @and .temperature responsive means inear :said -,other 1 end for .con-` trollingsaid cooling means.y

1.6. In an incubator .having an elongated v,pas-.

vsage formed by wall means, means for progresheat `.archange .mea-ns Ydis.tributed- .along .the length-of saidpassageandin heat exchange -izelation with said vWall means, means for `circulate ing heat .exchange ;me.dum.;.serial 1y through said .heatfenohangemeans means .responsive to temperature at ...each .end =of said passage :ooolihg .means for. said. medium .controlled Joy one ,Qi-said temperature responsive means, heating means. for f said mediumk controlled .by the other o f said. temperature responsive means, gancir means for passing Ventilating air in heat exchangezrelation with said wall .means-and transversely across said passage andsaid egg advancing vmeans.

.Roaster B. r. CRAWFORD.

.EEFERENQES ICIIED The. following f-refierenoes are .ofgrecord iin the ille @of thisaterrt:

UNITED STATES PATENTS Number .Name Y Date 5,294 'Cantale .Ju1y 24 1841 .27156356- Winkler Y rQct. 16, .1883 .3.lih36 Worswick Aiigtll. 18.86 143513.87, Bishop Sept..2 189.0 49,1 Q'I .rMoAslaii .May Y 2.5,. 189.5. 11,543 Wilson geputzt, 189g v.673,882 Horral July 2-3, 190,1 692,277 I-Iall Feb. 4, Y1902 798,697 Perkins sept. 5,A 1905 :926,434 McCabe June 29, 1909 `1,015,290 Bryant Jen, 23, 19.12 110841345 .Jonesn Jan. l13, 1914 A134109.,.520 .Bird.g i Mar. f14, `1922 1,262,860- v 1918 1;.5615413 19.28 1,"7.781v66. n n V19.30 .1,815,510 193.1 52,131,996 s 1938 2,18335170- Collins., Jan. 1.6, 1940 .2,334,855 l.Gravv-forel v Nov. 23, 119e?, 

